Renal granuloma as an extraintestinal manifestation in Crohn’s disease: A case report

Figure 1 Renal biopsy showing features (marked with arrows and circles) of acute interstitial nephritis and a single granuloma. A: Interstitial nephritis (hematoxylin and eosin, 100 ×); B: Granuloma (hematoxylin and eosin, 200 ×); C: Tubulitis with lymphocytes infiltrating a renal tubule (hematoxylin and eosin, 400 ×); D: Interstitial inflammation with eosinophils (hematoxylin and eosin, 400 ×).

Figure 2 Serial colonoscopy investigations. A: Index colonoscopy with normal terminal ileum, erythematous and featureless colon in all segments with rectal sparing; B: Healed colon one-year post infliximab therapy.

Figure 3 Improvement in estimated glomerular filtration rate and creatinine post infliximab induction and on maintenance therapy. Note that at 18 months there was a decline in renal function (estimated glomerular filtration rate 66 mL/minute, creatinine 132 μmol/L) - this corresponded to an increase in bowel frequency (without per rectal bleeding and urgency) and coincided with planned de-escalation in infliximab to fortnightly from weekly treatment. Subsequent escalation to weekly infliximab led to resolution of gastrointestinal symptoms and improved renal function. eGFR: Estimated glomerular filtration rate.